Last Modified: 11-20-2023 6.11:8.1.0 Doc ID: RM1000000013PZF
Model Year Start: 2018 Model: Camry Prod Date Range: [03/2017 -           ]
Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System): Pressure Sensor Circuit; 2018 - 2024 MY Camry [03/2017 -        ]

Pressure Sensor Circuit

DESCRIPTION

Based on signals from the air conditioner pressure sensor, the air conditioning amplifier assembly controls the compressor assembly with pulley (compressor solenoid)*1 or cooler compressor assembly (compressor solenoid)*2 and changes the air inlet mode between fresh and recirculation in order to protect the parts of the refrigerant cycle.

  • *1: for A25A-FKS
  • *2: for 2GR-FKS

WIRING DIAGRAM

PROCEDURE

1.

CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)

*a

Front view of wire harness connector

(to Air Conditioner Pressure Sensor)

(a) Disconnect the A18 air conditioner pressure sensor connector.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

A18-3 (+) - Body ground

Ignition switch ON

4.75 to 5.25 V

NG

GO TO STEP 6

OK

2.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - BODY GROUND)

*a

Front view of wire harness connector

(to Air Conditioner Pressure Sensor)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A18-1 (-) - Body ground

Always

Below 1 Ω

NG

GO TO STEP 5

OK

3.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the K55 air conditioning amplifier assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A18-2 (PR) - K55-24 (PRE)

Always

Below 1 Ω

A18-2 (PR) or K55-24 (PRE) - Other terminals and body ground

Always

10 kΩ or higher

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.

INSPECT AIR CONDITIONER PRESSURE SENSOR (SENSOR SIGNAL CIRCUIT)

*a

Component with harness connected

(Air Conditioning Amplifier Assembly)

(a) Measure the voltage with the following conditions met.

Measurement Condition:

Item

Condition

Vehicle doors

Fully open

Temperature setting

MAX COLD

Blower speed

HI

A/C switch

On

Recirculation/fresh switch

RECIRCULATION

Interior temperature

25 to 35°C (77 to 95°F)

NOTICE:

  • If refrigerant pressure on the high pressure side becomes extremely high during the inspection (if the voltage exceeds 4.61 V), a fail-safe function will stop compressor operation. In this case, make sure to measure the voltage before the fail-safe function operates.
  • It is necessary to measure the voltage for a certain amount of time (approximately 10 minutes) because the malfunction may recur after a while.

HINT:

When the ambient air temperature is low (below -1.5°C (29.3°F)), the compressor with pulley will be stopped, due to inputs of the thermistor assembly and No. 1 cooler thermistor, to prevent the evaporator from freezing. In this case, perform the inspection in a warm indoor environment.

(1) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

K55-24 (PRE) - Body ground

Ignition switch ON

(A/C switch: On)

0.74 to 4.61 V

(b) Connect the Techstream to the DLC3.

(c) Turn the ignition switch to ON.

(d) Turn the Techstream on.

(e) Enter the following menus: Body Electrical / Air Conditioner / Data List.

(f) Read the Data List according to the display on the Techstream.

Body Electrical > Air Conditioner > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Regulator Pressure Sensor

Air conditioner pressure sensor

Min.: -456.68 kPaG

Max.: 3294.37 kPaG

Actual refrigerant pressure displayed

-

Body Electrical > Air Conditioner > Data List

Tester Display

Regulator Pressure Sensor

OK:

The voltage and value displayed in the Data List change.

Result

Proceed to

OK

A

NG (The voltage changes but the value displayed in the Data List does not change.)

NG (The voltage does not change.)

B

A

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 2018 MY Camry [03/2017 - 06/2017]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL 2018 - 2024 MY Camry [06/2017 -        ]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL

B

REPLACE AIR CONDITIONER PRESSURE SENSOR 2018 MY Camry [03/2017 - 06/2017]; HEATING / AIR CONDITIONING: AIR CONDITIONING PRESSURE SENSOR: REMOVAL 2018 - 2020 MY Camry [06/2017 - 10/2020]; HEATING / AIR CONDITIONING: AIR CONDITIONING PRESSURE SENSOR: REMOVAL 2021 - 2024 MY Camry [10/2020 -        ]; HEATING / AIR CONDITIONING: AIR CONDITIONING PRESSURE SENSOR: REMOVAL

5.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the K55 air conditioning amplifier assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K55-3 (SG-4) - A18-1 (-)

Always

Below 1 Ω

K55-3 (SG-4) or A18-1 (-) - Other terminals and body ground

Always

10 kΩ or higher

OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 2018 MY Camry [03/2017 - 06/2017]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL 2018 - 2024 MY Camry [06/2017 -        ]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

6.

CHECK HARNESS AND CONNECTOR (AIR CONDITIONER PRESSURE SENSOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)

(a) Disconnect the K55 air conditioning amplifier assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

K55-6 (S5-3) - A18-3 (+)

Always

Below 1 Ω

K55-6 (S5-3) or A18-3 (+) - Other terminals and body ground

Always

10 kΩ or higher

OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY 2018 MY Camry [03/2017 - 06/2017]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL 2018 - 2024 MY Camry [06/2017 -        ]; HEATING / AIR CONDITIONING: AIR CONDITIONING AMPLIFIER: REMOVAL

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR